Most of the time I just shoot it out. But sometimes I use a ball puller and pull the load out that way.
During deer season my ML's are always loaded. After I shoot at a game animal that ML is completely cleaned and dried. Then it's reloaded until my next shot opportunity.
Depends on your muzzleloader. I have an Optima and I just remove the plug, place a bag over the opening to catch the powder (Blackhorn 209), not needed if you shoot pellets, and push the bullet and sabot out the back of the gun.
There is also a small unloader that works off a Co2 cylinder. It blows the whole load out the end. It doesn’t have alot of velocity. You can shoot the cylinder in a pillow and save the bullet for another day. You still have to run a patch or 3 thru it. The Co2 is cold air and creates moisture. I use one on my side hammer. They are cheap and real handy.
I never unload mine at the end of the day unless I've just been sitting in an absolute drenching downpour for hours. Sometimes not even then. A few times over the years, I've left a ML loaded from one season to the next and it went bang just fine.